Lakes / Oregon / Klamath County / Threemile Reservoir
Threemile Reservoir, Klamath County, Oregon
130 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - Oregon
42.04 degrees N, 121.16 degrees W - Klamath County. State and county outlines drawn from Census boundary data; the lake marker is placed by its USGS National Hydrography Dataset coordinates, not by eye. Schematic - not a survey map.
How Threemile Reservoir Stacks Up
- Larger than 64% of the 642 lakes counted in Oregon.
- About 90 miles from Medford, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Bumphead Reservoir | Klamath | 3.0 mi | 43 acres |
| Willow Valley Reservoir | Klamath | 3.4 mi | 543 acres |
| Copeland Reservoir | Klamath | 4.3 mi | 78 acres |
| Boggs Lake | Klamath | 4.4 mi | 57 acres |
| Dog Hollow Reservoir | Klamath | 6.0 mi | 45 acres |
| Twenty One Reservoir | Klamath | 6.3 mi | 30 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Threemile Reservoir
How Big Is Threemile Reservoir?
Threemile Reservoir covers 130 acres in Klamath County, Oregon.
What Is the Largest Lake in Klamath County?
Upper Klamath Lake is the largest lake in Klamath County, at 62,095 acres.
Largest Lakes in Oregon
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Upper Klamath Lake | Klamath | 62,095 acres | - |
| 2 | Lake Umatilla | Morrow | 50,042 acres | - |
| 3 | Lake Abert | Lake | 37,137 acres | - |
| 4 | Summer Lake | Lake | 31,602 acres | - |
| 5 | Harney Lake | Harney | 31,290 acres | - |
All 642 Oregon lakes ranked by surface area
Sources: USGS NHD (The National Map NHD MapServer layer 12) named waterbodies FTYPE 390/436; counties via Census point-in-polygon lake data (ID 84069977). Verified October 30, 2026.